The present invention relates to industrial safety devices, and more particularly to an air lockout device for an air driven fixture.
Today's industrial manufacturing facilities rely heavily on air driven fixtures for machining and other processes. Air driven fixtures are powered by pressurized air to perform a variety of tasks such as grinding, cutting, and drilling. Over the years, safety regulations have been developed to govern the use of air driven fixtures. These regulations are designed to protect the safety and well-being of operators, servicemen, and others who may work with or in the vicinity of air driven fixtures. Typical safety regulations require that an air driven fixtures be locked out from the air supply during set-up, adjustment, repair, service, installation, and maintenance. Essentially, this regulation requires some type of mechanism for preventing unauthorized, accidental, or inadvertent connection of an air supply line to the fixture. Additionally, these regulations generally require a mechanism for releasing the pressurized air built-up within the fixture. If not released, this air could cause unintended operation of the fixture or unpredictable results during disassembly of the fixture.
A variety of air supply lockout devices have been developed to comply with these regulations. One type of commercially available air lockout device is a supply line lock box. The supply line lock box attaches to the supply line to prevent it from being connected to the fixture. The lock box includes a hinged shell that is closed over the end of the supply line to prevent access to the female fitting. Typically, the lock box includes a pair of ears or similar components that allow the lock box to be padlocked in place. A separate lock box must be installed on each supply line capable of supplying air to the fixture. Additionally, the lock box does nothing to release air pressure built-up in the fixture.
A second commercially available air lockout device is a locking valve. The locking valve is installed on the fixture between the male inlet and the operating components of the fixture. The locking valve includes a relatively complex bleeder arrangement that allows the pressurized air built-up in the fixture to be released as the valve is closed. Once closed, the valve can be padlocked in position to prevent inadvertent or unauthorized supply of air to the fixture. The locking valve is relatively expensive to purchase and install because a separate valve must be added to each fixture.